The enhanced Distributed Channel Access (EDCA) of the Institute of Electrical and Electronics Engineers (IEEE) standard 802.11 is an enhancement to the original IEEE 802.11 Media Access Control (MAC) sublayer and is a method of medium access described in the standard amendment document IEEE 802.11e. EDCA provides four prioritized queues for transmission, where each queue is associated with a different access category (AC). The four access categories defined, for example, in IEEE standard 802.11e, in decreasing priority, are AC_VO, AC_VI, AC_BE and AC_BK, named for voice traffic, video traffic, best-effort traffic, and background traffic, respectively. The queues use a contention-based mechanism to determine the next frame for transmission. The queue parameters are set such that the high priority queues have a preference for access to the wireless medium.
Management frames are the foundation of network management traffic in a Wireless Local Area Network (WLAN). Current IEEE 802.11 standards dictate that, in any access point (AP) or non-AP station (STA), management frames are to be handled via the EDCA queue of highest priority.